What Are Backlinks? How They Work and How to Earn Them

Backlinks are links on other websites that point to pages on yours. Google uses links as a signal when it judges how relevant a page is, and to find new pages to crawl ^[1]. A backlink from a relevant, trusted site works like a public recommendation. The method fits in one line: publish pages worth citing, find the sites that already link to pages like yours, and ask them for a link, never pay for one. Relevance beats raw count, because many shortcut link sources count as spam.

What are backlinks in SEO, and why do they matter?

Every backlink has four parts. There is the page that links, the page on your site it points to, the clickable words (the anchor text), and an optional rel attribute that tells Google how to treat the link. Links between pages of your own site are internal links, not backlinks. Website backlinks come from other domains, and SEO tools count them two ways: total links, and referring domains, the number of distinct sites linking to you.

Referring domains usually tell you more. One partner blog that links to you from 200 pages in its sidebar adds 200 backlinks but only one referring domain. Ten local news sites that each mention you once add ten. When people ask what SEO backlinks are, this is the practical answer: votes from separate, relevant sites. Search engines read them as evidence that people outside your company find your pages useful.

Links also do a second job. They send real visitors, and those visitors arrive already curious. A link on a page your customers read brings traffic even if it carries no ranking weight at all. That is why good link building starts with the question would a reader click this? rather than will Google count this?

What makes a backlink worth having

Not all links are equal. Four traits separate a useful backlink from noise. First, topical relevance: a link from a site about your subject means more than one from an unrelated page. Second, editorial placement: the link sits inside the content because the author chose it, not in a footer or a sitewide widget. Third, a site with a real audience. Fourth, descriptive anchor text.

Google says good anchor text is descriptive, reasonably concise and relevant to both the page it sits on and the page it links to. It also warns that stuffing keywords into anchors breaks its spam policies. So a link reading sourdough baking classes in Austin helps people and search engines. A dozen links that all repeat one exact keyword phrase look manufactured.

The rel attribute changes how Google treats a link. Site owners are asked to mark some links so they don't pass endorsement ^[2]:

Links marked with these values are generally not followed. They still have value when they bring readers, so don't turn down a nofollow mention on a popular site.

Link building: a five-step method

Link building is the work of earning backlinks on purpose. For a small business or a blog, it doesn't need a specialist. It needs a repeatable routine you run every month, with a short list of targets and a record of who you contacted. These five steps cover it.

1. Check what you already have. Verify your site in Google Search Console and open the Links report, which lists top linking sites, top linked pages and top linking text. Our guide on how to check backlinks for free walks through it screen by screen.
2. Pick pages worth linking to. Original data, a local guide, a calculator, a clear how-to. Nobody links to a product page out of kindness.
3. Find prospects. Look for sites that link to two or three of your competitors but not to you. Look for dead links on relevant pages that your content could replace. Search for mentions of your brand that carry no link.
4. Reach out personally. Write a short email that names the exact page, says why your resource helps their readers, and asks once. Follow up one time, then move on.
5. Track and repeat. Each month, note new and lost links. A lost link from a good site is worth a polite email while the page is still fresh in the owner's memory.

Steps 1 and 5 are free for your own site. Step 3 is where most of the time goes, because finding who links to your competitors needs a backlink index that covers other sites.

A link building example: a local bakery

Picture a bakery in Austin with a website, a blog and almost no links. Its Search Console Links report shows a handful of referring domains: two directories, a supplier and an old event page. The owner decides the bakery's best linkable asset is a free guide to the city's farmers markets, updated each season, with opening hours and parking tips.

She then makes a prospect list with a backlink checker that covers other sites. Three rival bakeries are linked from food blogs, a neighborhood association and a wedding-planning site. Two of those blogs also link to a farmers-market page that now returns an error. She emails each site once, offering her guide as a replacement or an addition. Over a season, she earns links from four of them, all relevant, all editorial.

Nothing here is clever. The work is a good page, a list of sites that already care about the topic, and a polite ask. That is how most durable website backlinks are earned.

Backlink mistakes Google treats as link spam

Google defines link spam as creating links to or from a site mainly to manipulate rankings ^[3]. Its examples cover most shortcuts sold to small businesses. Avoid these:

• Buying or selling links for ranking, including trading goods or services for them, or sending a free product in exchange for a post with a link.
• Excessive link exchanges, the link to me and I'll link to you deal, or partner pages that exist only for cross-linking.
• Automated link building with programs or services that create links for you.
• Low-quality directories and bookmark sites.
• Keyword-rich links in widgets, footers or templates spread across many sites.
• Forum comments with optimized links in the post or signature.

The fix for a paid placement is simple: the site should mark it sponsored. That keeps a sponsorship honest without any ranking risk.

Spammy links from strangers are a different story. Every site collects some. Google says it can usually work out which links to trust on its own, so most sites never need to disavow anything ^[4].

When building website backlinks gets hard

The free method breaks down at a specific point. Google Search Console shows links to your own verified site only, and Google calls the Links report a sample, with each table capped at 1,000 rows. Our walkthrough of the Search Console links report shows what it can and cannot tell you. The moment you need step 3, a list of who links to your competitors, Search Console has nothing to offer.

That gap usually shows up once you have a few pages worth promoting and two or three clear competitors. Agencies hit it on day one, since every client needs a prospect list. A backlink tool fills it with a competitor comparison report and a broken-link finder, and it tracks new and lost links without a monthly spreadsheet. Ahrefs, for example, uses Link Intersect to show sites that link to competitors but not to you.

For a side-by-side look at how each backlink checker covers checking, prospecting and monitoring, see our guide to backlink checker tools.

The bottom line

Backlinks are links from other sites to yours, and Google reads them as a signal of relevance and as a path to new pages. Good ones are relevant, editorial and described by honest anchor text. Earn them with a simple monthly routine: check your links, build one page worth citing, find sites that link to your competitors, ask politely, and track what you gain and lose. Skip paid links and link schemes. Search Console covers your own site; competitor prospecting is where a backlink tool starts to pay off in saved hours.